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Ventricular diverticula are saccule-like structures formed by the protrusion of the ventricular myocardium from the endocardial surface towards the free wall. Most diverticula are muscular structures, and patients usually have no obvious clinical symptoms. However, diverticula may contribute to arrhythmogenesis due to localized myocardial structural disturbances. Right ventricular apical diverticulum (RVAD) is very rare, and we report a case of highly symptomatic accelerated idioventricular rhythm (AIVR) originating from the RVAD that underwent intracardiac echocardiography (ICE)-guided catheter ablation with no recurrence during follow-up.
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OBJECTIVE: To compare the trueness of incisal guidance of implant-supported single crowns designed by patient-specific motion (PSM) with that designed by average-value virtual articulator (AVA). METHODS: The study had recruited 12 participants with complete dentition and stable incisal guidance. An intraoral scanner was used to scan digital casts and record two types of patient-specific motion (data only including protrusive movement, and data including protrusive movement and lateral protrusive movement). The lingual surfaces of the maxillary incisors which guided the protrusive movement was selected and elevated to create a reference cast. A maxillary central incisor of original casts was vir-tually extracted and implanted to generate a working cast. The Dental system software program was used to design implant-supported single crowns with the anatomical coping design method. The incisal guidance was designed by different methods. The incisal guidance in control group was designed by the average-value virtual articulator. The incisal guidance in experiment groups was designed by the patient-specific motion only including protrusive movement (PSM1) and with the patient-specific motion including protrusive movement and lateral protrusive movement (PSM2). The incisal guidance of prosthesis designed by these 3 methods were compared with the original incisal guidance in Geomagic Control 2015 (3DSystem, America). The measurements included: Average of positive values, ratio of positive area and maximum value reflecting supra-occlusion; average of negative values, ratio of negative area and minimum value reflecting over-correction; and root mean square reflecting overall deviation. RESULTS: Statistical data were collected using the median (interquartile range) method. The average of positive values, ratio of positive area and average of negative values of the PSM2 group were smaller than those of the control group [8.0 (18.8) µm vs. 37.5 (47.5) µm; 0 vs. 7.2% (38.1%); -109.0 (63.8) µm vs.-66.5 (64.5) µm], and the ratio of negative area of PSM2 group was larger than those of the control group [52.9% (47.8%) vs. 17.3% (45.3%)], with significant differences (P all < 0.05). The ratio of positive area [0.1% (7.0%)] and average of negative values [-97.0 (61.5) µm] of PSM1 group, were smaller than those of the control group, and the ratio of negative area [40.7% (39.2%)] of the PSM1 group was larger than that of the control group, with significant differences (P < 0.05). The average of positive values [20.0 (42.0) µm] and ratio of positive area of PSM1 group was larger than that of the PSM2 group with significant differences (P < 0.05). CONCLUSION: To establish the incisor guidance of implant-supported single crowns, compared with the average-value virtual articulator and the patient-specific motion only including protrusive movement, the patient-specific motion including protrusive movement and lateral protrusive movement is more conducive to reducing the protrusive interference of prosthesis and improving the occlusal fit.
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Incisivo , Software , Humanos , Maxila , Coroas , Movimento , Desenho Assistido por ComputadorRESUMO
Mitochondrial division inhibitor 1(Mdivi-1) has been shown to play a beneficial role in a variety of diseases, mainly by inhibiting Drp1-mediated mitochondrial fission. The effects of Mdivi-1 on cardiac fibrosis at infarcted border zone area and its possible mechanism remain unclear. This study aimed to investigate the effects of Mdivi-1 on reactive cardiac fibrosis and cardiac function post myocardial infarction and its potential mechanisms. Mice were randomly divided into six groups (n = 9 for each group): Sham; Mdivi-1; MI 7d; MI 14d; MI 28d; MI 28d + Mdivi-1. The MI model was induced by ligation of LAD coronary artery. Mdivi-1 (1 mg/kg) was administered to mice every other day at a time from the second day until the sacrifice of the mice (total 14 injection of Mdivi-1). In vitro experiments, the effect of Mdivi-1 on TGF-ß1-induced fibrosis-related pathophysiological changes of fibroblasts was examined in NIH3T3 cells. We found that Mdivi-1 significantly attenuated fibroblast activation, collagen production and fibrosis at infarcted border zone after MI, improved impaired heart function. Mechanistically, we observed that Mdivi-1 reduced the protein expression of P-Drp1-S616 and abnormal mitochondrial fission of cardiac fibroblasts in the infarcted border zone area. In addition, we found that the effects of Mdivi-1 partially relied on increasing the expression of Hmox1 and inhibiting oxidative stress. In conclusion, Mdivi-1 could attenuate cardiac fibrosis at infarcted border zone and improve impaired heart function partially through attenuation of Drp1-mediated mitochondrial fission. Moreover, inhibition of oxidative stress, which is possible due to the up-regulation of Hmox1, may be another potential mechanism of action of Mdivi-1.
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Dinâmica Mitocondrial , Infarto do Miocárdio , Animais , Dinaminas/metabolismo , Fibrose , Camundongos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/metabolismo , Células NIH 3T3 , Estresse Oxidativo , Quinazolinonas/farmacologia , Quinazolinonas/uso terapêuticoRESUMO
PURPOSE: The combined use of antibiotics and anti-inflammatory medicine to manage bacterial endotoxin-induced inflammation following injuries or diseases is increasing. The cytokine level produced by macrophages plays an important role in this treatment course. Ciprofloxacin and indomethacin, two typical representatives of antibiotics and anti-inflammatory medicine, are cost-effective and has been reported to show satisfactory effect. The current study aims to investigate the effect of ciprofloxacin along with indomethacin on the secretion of inflammatory cytokines by macrophages in vitro. METHODS: Primary murine peritoneal macrophages and RAW 264.7 cells were administrated with lipopolysaccharide (LPS) for 24 h. The related optimal dose and time point of ciprofloxacin or indomethacin in response to macrophage inflammatory response inflammation were determined via macrophage secretion induced by LPS. Then, the effects of ciprofloxacin and indomethacin on the secretory functions and viability of various macrophages were determined by enzyme-linked immunosorbent assay and flow cytometry analysis, especially for the levels of interleukin (IL)-1ß, IL-6, IL-10, and tumor necrosis factor (TNF)-α. The optimal dose and time course of ciprofloxacin affecting macrophage inflammatory response were determined by testing the maximum inhibitory effect of the drugs on pro-inflammatory factors at each concentration or time point. RESULTS: According to the levels of cytokines secreted by various macrophages (1.2 × 106 cells/well) after administration of 1 µg/mL LPS, the optimal dose and usage timing for ciprofloxacin alone were 80 µg/mL and 24 h, respectively, and the optimal dose for indomethacin alone was 10 µg/mL. Compared with the LPS-stimulated group, the combination of ciprofloxacin and indomethacin reduced the levels of IL-1ß (p < 0.05), IL-6 (p < 0.05), IL-10 (p < 0.01)), and TNF-α (p < 0.01). Furthermore, there was greater stability in the reduction of inflammatory factor levels in the combination group compared with those in which only ciprofloxacin or indomethacin was used. CONCLUSION: The combination of ciprofloxacin and indomethacin suppressed the levels of inflammatory cytokines secreted by macrophages in vitro. This study illustrates the regulatory mechanism of drug combinations on innate immune cells that cause inflammatory reactions. In addition, it provides a new potential antibacterial and anti-inflammatory treatment pattern to prevent and cure various complications in the future.
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Citocinas , Lipopolissacarídeos , Humanos , Camundongos , Animais , Lipopolissacarídeos/farmacologia , Interleucina-10 , Indometacina/farmacologia , Indometacina/uso terapêutico , Interleucina-6/farmacologia , Interleucina-6/uso terapêutico , Ciprofloxacina/farmacologia , Ciprofloxacina/uso terapêutico , Macrófagos , Fator de Necrose Tumoral alfa , Inflamação/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antibacterianos/uso terapêuticoRESUMO
In the last decades, a kind of small non-coding RNA molecules, called as microRNAs, has been applied as negative regulators in various types of cancer treatment through down-regulation of their targets. More recent studies exert that microRNAs play a critical role in the EMT process of cancer, promoting or inhibiting EMT progression. Interestingly, accumulating evidence suggests that pure compounds from natural plants could modulate deregulated microRNAs to inhibit EMT, resulting in the inhibition of cancer development. This small essay is on the purpose of demonstrating the significance and function of microRNAs in the EMT process as oncogenes and tumor suppressor genes according to studies mainly conducted in the last four years, providing evidence of efficient target therapy. The review also summarizes the drug candidates with the ability to restrain EMT in cancer through microRNA regulation.
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Antineoplásicos/farmacologia , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Animais , Humanos , MicroRNAs/genética , Neoplasias/genética , Neoplasias/patologia , Transdução de SinaisRESUMO
OBJECTIVE: To investigate the relationship between angiotensin â -converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism and the genetic risks for polycystic ovary syndrome (PCOS) and to evaluate the impact of ACE I/D genotypes on clinical, hormonal, metabolic and oxidative stress parameters in patients with PCOS. METHODS: This was a retrospective case-control study involving a total of 1 020 PCOS patients and 825 female controls who visited the outpatient clinic of the Department of Reproductive Endocrinology, West China Second Hospital of Sichuan University between 2006 and 2019. The ages of the subjects ranged between 17 and 44. The ACE I/D genotypes were determined by polymerase chain reaction (PCR) and gel electrophoresis. 667 PCOS patients and 527 controls were selected for an analysis of their genotypes and the hormonal, metabolic and oxidative stress parameters. RESULTS: The genotype distributions of the ACE I/D single nucleotide polymorphism was in Hardy-Weinberg equilibrium in both the PCOS group and the control group (all P>0.05), which was representative of the population. There were no statistically significant differences in genotype and allele frequencies between the PCOS and the control groups ( P>0.05). After adjusting for both age and body mass index (BMI), there was no statistically significant difference in clinical characteristics among all genotypes in either the PCOS group or the control group. In the PCOS group, compared with the II genotype subgroup, the ID genotype subgroup had lower luteinizing hormone (LH)/follicle-stimulating hormone (FSH) ratio, while the DD genotype subgroup had higher homeostatic model assessment of insulin resistance (HOMA-IR) and malondialdehyde (MDA) levels. Compared with the ID genotype subgroup, the DD genotype subgroup had lower serum sex hormone binding globulin (SHBG) level, but higher total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels ( P<0.05). In the control group, II genotype subgroup had a higher level of total oxidant status (TOS) than that of the DD genotype subgroup. CONCLUSION: ACE I/D genetic polymorphism is not associated with risks for PCOS. The I/D variation of ACE gene may be related to insulin resistance, dyslipidaemia, hyperandrogenemia and oxidative stress in PCOS patients.
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Peptidil Dipeptidase A/genética , Síndrome do Ovário Policístico , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Síndrome do Ovário Policístico/genética , Polimorfismo de Nucleotídeo Único , Estudos RetrospectivosRESUMO
Cancer stem-like cells are rare immortal cells within tumor, which are thought to play important roles in ionizing radiation (IR) therapy-resistance. Quercetin is a natural flavonoid with potential anti-cancer properties without significant cytotoxicity in normal tissues. In this study, we demonstrated that quercetin-IR combination treatment exhibited more dramatic anti-cancer effect than either quercetin or IR treatment alone via targeting colon cancer stem cells (CSCs) and inhibiting the Notch-1 signaling. These effects were further verified by in vivo studies which showed remarkable decrease of the CSCs markers and the expression of Notch-1 signaling proteins in human colon cancer xenografts in nude mice. Co-treatment with quercetin and low dose of radiation significantly reduced the expressions of all five proteins of γ-secretase complex in HT-29 and DLD-1 cells. In addition, ectopic expression of the Notch intracellular domain (NICD) partly reversed the inhibition effects by the combination therapy. In conclusion, our results indicated that the combination of quercetin (20 µM) and IR (5Gy) might be a promising therapeutic strategy for colon cancer treatment by targeting colon cancer stem-like cells and inhibiting the Notch-1 signaling. In future studies, we intend to further explore the potential therapeutic efficacy of the quercetin-radiation combination treatment in clinical trials.
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Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/radioterapia , Quercetina/uso terapêutico , Tolerância a Radiação/efeitos dos fármacos , Receptores Notch/metabolismo , Transdução de Sinais , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/efeitos da radiação , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Quercetina/farmacologia , Tolerância a Radiação/efeitos da radiação , Radiação Ionizante , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The mangrove-derived endophytic fungus Peniophora incarnata Z4 produced seven new xanthone derivatives, including four new tetrahydroxanthones (1-4), one new chromone (5), one new xanthone (6), and one new xanthone dimer (7), together with one known compound, globosuxanthone B (8). Their structures were determined by an extensive analysis of 1D and 2D NMR, HRESIMS, ECD, and single-crystal X-ray diffraction data. In cytotoxic activity assays, compound 2 showed cytotoxicity against three carcinoma cell lines with IC50 values less than 10 µM.
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Basidiomycota , Estrutura Molecular , Xantonas , Antineoplásicos , Cromonas , Cristalografia por Raios X , EndófitosRESUMO
In order to discover and develop the new HIV-1 NNRTIs, a series of 5-alkyl-6-(benzo[d][1,3]dioxol-5-ylalkyl)-2-mercaptopyrimidin-4(3H)-ones was synthesized and screened for their in vitro cytotoxicity against HIV-1. Most of the compounds we synthetized showed high activity against wild-type HIV-1 strain (IIIB) while IC50 values are in the range of 0.06-12.95 µM. Among them, the most active HIV-1 inhibitor was compound 6-(benzo[d][1,3]dioxol-5-ylmethyl)-5-ethyl-2-((2-(4-hydroxyphenyl)-2-oxoethyl)thio)pyrimidin-4(3H)-one (5b), which exhibited similar HIV-1 inhibitory potency (IC50 = 0.06 µM, CC50 = 96.23 µM) compared with nevirapine (IC50 = 0.04 µM, CC50 >200 µM) and most of compounds exhibited submicromolar IC50 values indicating they were specific RT inhibitors. The compounds 5b, 6-(benzo[d] [1,3]dioxol-5-yl)-5-ethyl-2-((2-(4-hydroxyphenyl)-2-oxoethyl)thio)pyrimidin-4(3H)-one (5c) and 4-(2-((4-(benzo[d][1,3]dioxol-5-ylmethyl)-5-ethyl-6-oxo-1,6-dihydropyrimidin-2-yl)thio)acetyl)phenylbenzo[d][1,3]dioxole-5-carboxylate (5r) were selected for further study. It was found that all of them had little toxicity to peripheral blood mononuclear cell (PBMC), and had a good inhibitory effect on the replication of HIV-1 protease inhibitor resistant strains, fusion inhibitor resistant strains and nucleosides reverse transcriptase inhibitor resistant strains, as well as on clinical isolates. Besides, compound 5b and 5c showed inhibition of HIV-1 RT RNA-dependent DNA polymerization activity and DNA-dependent DNA polymerization activity, while compound 5r only showed inhibition of HIV DNA-dependent DNA polymerization activity, which was different from classical reverse transcriptase inhibitors. Our study which offered the preliminary structure-activity relationships and modeling studies of these new compounds has provided the valuable avenues for future molecular optimization.
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Fármacos Anti-HIV/uso terapêutico , HIV-1/efeitos dos fármacos , Pirimidinonas/química , Inibidores da Transcriptase Reversa/uso terapêutico , Fármacos Anti-HIV/farmacologia , Desenho de Fármacos , Humanos , Modelos Moleculares , Inibidores da Transcriptase Reversa/farmacologia , Relação Estrutura-AtividadeRESUMO
BACKGROUND: Strong epidemiologic evidence indicates that green tea intake is protective against hyperlipidemia; however, randomized controlled studies have presented varying results. In the present study, we aimed to conduct a literature review and meta-analysis to assess the effect of green tea on blood lipids. METHODS: PubMed, Embase, and the Cochrane Library were electronically explored from inception to September 2019 for all relevant studies. Random effect models were used to estimate blood lipid changes between green tea supplementation and control groups by evaluating the weighted mean differences (WMD) with 95% confidence intervals (CIs). The risk of bias for study was assessed using the Cochrane tool. Publication bias was evaluated using funnel plots and Egger's tests. RESULTS: Thirty-one trials with a total of 3321 subjects were included in the meta-analysis. In general, green tea intake significantly lowered the total cholesterol (TC); WMD: - 4.66 mg/dL; 95% CI: - 6.36, - 2.96 mg/dL; P < 0.0001) and low-density lipoprotein (LDL) cholesterol (WMD:- 4.55 mg/dL; 95% CI: - 6.31, - 2.80 mg/dL; P < 0.0001) levels compared with those in the control. Green tea consumption did not affect high-density lipoprotein (HDL) cholesterol; however, it reduced the triglycerides compared with that in the control (WMD: - 3.77 mg/dL; 95% CI: - 8.90, 1.37 mg/dL; P = 0.15). In addition, significant publication bias from funnel plots or Egger's tests was not evident. CONCLUSIONS: Collectively, consumption of green tea lowers LDL cholesterol and TC, but not HDL cholesterol or triglycerides in both normal weight subjects and those who were overweight/obese; however, additional well-designed studies that include more diverse populations and longer duration are warranted.
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Lipídeos , Chá , HDL-Colesterol , LDL-Colesterol , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Purine nucleoside phosphorylases (PNPs) are promising biocatalysts for the synthesis of purine nucleoside analogs. Although a number of PNPs have been reported, the development of highly efficient enzymes for industrial applications is still in high demand. Herein, a new trimeric purine nucleoside phosphorylase (AmPNP) from Aneurinibacillus migulanus AM007 was cloned and heterologously expressed in Escherichia coli BL21(DE3). The AmPNP showed good thermostability and a broad range of pH stability. The enzyme was thermostable below 55 °C for 12 h (retaining nearly 100% of its initial activity), and retained nearly 100% of the initial activity in alkaline buffer systems (pH 7.0-9.0) at 60 °C for 2 h. Then, a one-pot, two-enzyme mode of transglycosylation reaction was successfully constructed by combining pyrimidine nucleoside phosphorylase (BbPyNP) derived from Brevibacillus borstelensis LK01 and AmPNP for the production of purine nucleoside analogs. Conversions of 2,6-diaminopurine ribonucleoside (1), 2-amino-6-chloropurine ribonucleoside (2), and 6-thioguanine ribonucleoside (3) synthesized still reached >90% on the higher concentrations of substrates (pentofuranosyl donor: purine base; 20:10 mM) with a low enzyme ratio of BbPyNP: AmPNP (2:20 µg/mL). Thus, the new trimeric AmPNP is a promising biocatalyst for industrial production of purine nucleoside analogs.
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Bacillales/enzimologia , Nucleosídeos de Purina/metabolismo , Purina-Núcleosídeo Fosforilase/metabolismo , Bacillales/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biocatálise , Clonagem Molecular , Estabilidade Enzimática , Purina-Núcleosídeo Fosforilase/química , Purina-Núcleosídeo Fosforilase/genética , Pirimidina Fosforilases/metabolismo , TermodinâmicaRESUMO
BACKGROUND/AIMS: In recent years, microRNA-495 (miR-495) has been reported to be a tumor-suppressor miR that is down-modulated in cancers. However, its potential mechanism remains unknown. Therefore, this study aimed to demonstrate the role of miR-495 in cardiac microvascular endothelial cell (CMEC) injury and inflammatory reaction by mediating the pyrin domain-containing 3 (NLRP3) inflammasome signaling pathway. METHODS: Overall, 40 mice were assigned into myocardial ischemia/reperfusion injury (MIR) and sham groups. After model establishment, the levels of troponin T (TnT), troponin I (TnI), N-terminal pro-B-type natriuretic peptide (NT-proBNP), creatine kinase isoenzyme MB (CK-MB), myoglobin (MYO), tumor necrosis factor-alpha (TNF-α), and interleukin 1beta (IL-1ß) were detected by Enzyme-Linked Immunosorbent Assay (ELISA). Apoptosis was evaluated using Terminal deoxy (d)-UTP nick end labeling (TUNEL) staining, the level of NLRP3 protein was determined by immunohistochemical assay, and miR-495 was detected by in situ hybridization (ISH). The infarct size was determined using 2, 3, 5-triphenyltetrazolium chloride (TTC) staining. The expression of miR-495 and the mRNA and protein levels of NLRP3, TNF-α, IL-1ß, IL-18 and caspase-1 were evaluated by RT-qPCR and western blot analysis. After transfection, the cells were treated with a miR-495 mimic, a miR-495 inhibitor, or siNLRP3. Cell proliferation was measured by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and cell cycle and apoptosis by flow cytometry. RESULTS: Mice with myocardial I/R injury had elevated levels of TnT, TnI, NT-proBNP, CK-MB, MYO, TNF-α and IL-1ß; enhanced cell apoptosis; increased expression of NLRP3, TNF-α, IL-1ß, IL-18 and caspase-1; and decreased miR-495 expression. MiR-495 was confirmed to target NLRP3. Moreover, miR-495 reduced the mRNA and protein levels of NLRP3, TNF-α, IL-1ß, IL-18 and caspase-1, inhibited cell apoptosis and decreased cells at the G0/G1 phase while improving cell proliferation and increasing cells at the S phase. However, the effects of NLRP4 were proved to be reciprocal. CONCLUSION: In conclusion, the current study indicated that miR-495 improved CMEC injury and inflammation by suppressing the NLRP3 inflammasome signaling pathway.
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Inflamassomos/metabolismo , MicroRNAs/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais , Regiões 3' não Traduzidas , Animais , Antagomirs/metabolismo , Apoptose , Caspase 1/genética , Caspase 1/metabolismo , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular , Interleucina-18/genética , Interleucina-18/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismoRESUMO
Previous research has shown that the effectiveness of selecting filter sets from among a large set of commercial broadband filters by a vector analysis method based on maximum linear independence (MLI). However, the traditional MLI approach is suboptimal due to the need to predefine the first filter of the selected filter set to be the maximum â2 norm among all available filters. An exhaustive imaging simulation with every single filter serving as the first filter is conducted to investigate the features of the most competent filter set. From the simulation, the characteristics of the most competent filter set are discovered. Besides minimization of the condition number, the geometric features of the best-performed filter set comprise a distinct transmittance peak along the wavelength axis of the first filter, a generally uniform distribution for the peaks of the filters and substantial overlaps of the transmittance curves of the adjacent filters. Therefore, the best-performed filter sets can be recognized intuitively by simple vector analysis and just a few experimental verifications. A practical two-step framework for selecting optimal filter set is recommended, which guarantees a significant enhancement of the performance of the systems. This work should be useful for optimizing the spectral sensitivity of broadband multispectral imaging sensors.
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Dual energy computed tomography (DECT) can improve the capability of differentiating different materials compared with conventional CT. However, due to non-negligible radiation exposure to patients, dose reduction has recently become a critical concern in CT imaging field. In this work, to reduce noise at the same time maintain DECT images quality, we present an iterative reconstruction algorithm for low-dose DECT images where in the objective function of the algorithm consists of a data-fidelity term and a regularization term. The former term is based on alpha-divergence to describe the statistical distribution of the DE sinogram data. And the latter term is based on the redundant information to reflect the prior information of the desired DECT images. For simplicity, the presented algorithm is termed as "AlphaD-aviNLM". To minimize the associative objective function, a modified proximal forward-backward splitting algorithm is proposed. Digital phantom, physical phantom, and patient data were utilized to validate and evaluate the presented AlphaD-aviNLM algorithm. The experimental results characterize the performance of the presented AlphaD-aviNLM algorithm. Speficically, in the digital phantom study, the presented AlphaD-aviNLM algorithm performs better than the PWLS-TV, PWLS-aviNLM, and AlphaD-TV with more than 49%, 34%, and 40% gains for the RMSE metric, 1.3%, 0.4%, and 0.7% gains for the FSIM metric and 13%, 8%, and 11% gains for the PSNR metric. In the physical phantom study, the presented AlphaD-aviNLM algorithm performs better than the PWLS-TV, PWLS-aviNLM, and AlphaD-TV with more than 0.55%, 0.07%, and 0.16% gains for the FSIM metric.
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Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos , Pulmão/diagnóstico por imagem , Modelos Estatísticos , Imagens de Fantasmas , Radiografia TorácicaRESUMO
Five new p-terphenyls named prenylterphenyllin D (1), prenylterphenyllin E (2), 2'-O-methylprenylterphenyllin (3), 4-O-methylprenylterphenyllin (4) and 3'-O-methylterphenyllin (5) together with seven known compounds (6-12), were isolated from cultures of Aspergillus sp. YXf3. The structures of the new compounds were elucidated by extensive MS and NMR analyses. The NMR and MS data of 5 is reported for the first time, as its structure was listed in SciFinder Scholar with no associated reference. Compounds 6 and 7 were distinguished from each other on the basis of 2D NMR experiments. Compounds 1, 2, 3 and 8 showed antibacterial activities against X. oryzae pv. oryzicola Swings and E. amylovora with the same MIC values of 20µg/mL while 10 exhibited activities against E. amylovora with an MIC value of 10µg/mL.
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Antibacterianos/farmacologia , Aspergillus/química , Erwinia amylovora/efeitos dos fármacos , Compostos de Terfenil/farmacologia , Xanthomonas/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Compostos de Terfenil/química , Compostos de Terfenil/isolamento & purificaçãoRESUMO
The Pictet-Spengler (PS) reaction constructs plant alkaloids such as morphine and camptothecin, but it has not yet been noticed in the fungal kingdom. Here, a silent fungal Pictet-Spenglerase (FPS) gene of Chaetomium globosum 1C51 residing in Epinephelus drummondhayi guts is described and ascertained to be activable by 1-methyl-L-tryptophan (1-MT). The activated FPS expression enables the PS reaction between 1-MT and flavipin (fungal aldehyde) to form "unnatural" natural products with unprecedented skeletons, of which chaetoglines B and F are potently antibacterial with the latter inhibiting acetylcholinesterase. A gene-implied enzyme inhibition (GIEI) strategy has been introduced to address the key steps for PS product diversifications. In aggregation, the work designs and validates an innovative approach that can activate the PS reaction-based fungal biosynthetic machinery to produce unpredictable compounds of unusual and novel structure valuable for new biology and biomedicine.
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Alcaloides/biossíntese , Chaetomium/metabolismo , Chaetomium/genética , Genes FúngicosRESUMO
A 46-year-old man presented with recurrent left hemiparesis and headache. MRI of brain showed an acute right pontine and subacute right thalamic infarcts and MR angiogram showed multiple intracranial arterial stenoses, suggesting cerebral vasculopathy. There was a cerebrospinal fluid lymphocytic pleocytosis with Borrelia burgdorferi antibodies. Central nervous system Lyme disease occasionally presents with ischaemic strokes; this case is unusual in showing vasculopathy on brain imaging, supporting meningovasculitis as the likely mechanism.
Assuntos
Doença de Lyme/patologia , Doença de Lyme/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Isquemia Encefálica/complicações , Humanos , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To compare the advantages and disadvantages of the Foley catheter draining method versus the urethral stent plus gastric tube draining method for urine drainage following urethroplasty for hypospadias. METHODS: We retrospectively analyzed the clinical data of 361 cases of hypospadias treated by urethroplasty. After operation, 91 of the cases received urine drainage with the Foley catheter (group A) and 270 with a urethral stent plus a gastric tube (group B). We compared the incidence rates of bladder irritation, fistula, urethral stricture, and urethral diverticulum between the two groups of patients. RESULTS: No statistically significant differences were found between groups A and B in the incidences of bladder irritation (9.89% vs 10.70%, P > 0.05) and urethral diverticulum (1.09% vs 2.22%, P > 0.05). The incidence rate of fistula was markedly higher in group A than in B (20.80% vs 13.30%, P < 0.05), and so was that of urethral stricture (10.90% vs 5.55%, P < 0.05). CONCLUSION: The urethral stent plus gastric tube draining method is more effective than the Foley catheter draining method for urine drainage following urethroplasty.
Assuntos
Drenagem/métodos , Hipospadia/cirurgia , Stents , Uretra/cirurgia , Cateterismo Urinário/métodos , Idoso , Criança , Divertículo/etiologia , Humanos , Incidência , Masculino , Estudos Retrospectivos , Estreitamento Uretral/etiologia , Cateterismo Urinário/instrumentaçãoRESUMO
Gliomas are prevalent malignant tumors in adults, which can be categorized as either localized or diffuse gliomas. Glioblastoma is the most aggressive and deadliest form of glioma. Currently, there is no complete cure, and the median survival time is less than one year. The main mechanism of regulated cell death involves organisms coordinating the elimination of damaged cells at risk of tumor transformation or cells hijacked by microorganisms for pathogen replication. This process includes apoptosis, necroptosis, autophagy, ferroptosis, pyroptosis, necrosis, parthanayosis, entosis, lysosome-dependent death, NETosis, oxiptosis, alkaliptosis, and disulfidaptosis. The main goal of clinical oncology is to develop therapies that promote the effective elimination of cancer cells by regulating cell death are the main goal of clinical oncology. Recently, scientists have utilized pertinent regulatory factors and natural small-molecule compounds to induce regulated cell death for the treatment of gliomas. By analyzing the PubMed and Web of Science databases, this paper reviews the research progress on the regulation of cell death and the role of natural small-molecule compounds in glioma. The aim is to provide help for the treatment of glioblastoma.